The present invention relates to an automatic leveling method and an automatic leveling device, by which it is possible to perform a leveling on a tilt angle over a wide range with high accuracy by a simple structure.
In an apparatus, such as a surveying instrument, to which a leveling with high accuracy is required, a tilt sensor capable of detecting a horizontality with high accuracy is provided and the leveling is performed so that the apparatus becomes in horizontal position based on the signals from the tilt sensor.
However, in a tilt sensor with high accuracy, a detection range of the tilt angle is narrow and in a case where the tilt angle is large, a leveling cannot be performed. For this reason, in an automatic leveling device as used in the past, a high accuracy tilt sensor with highly accurate detection accuracy and a normal type tilt sensor which can detect a tilt angle in a wide range but with low accuracy are provided. In a case where the tilt angle exceeds the detection range of the high accuracy tilt sensor, a coarse leveling is performed based on detection results of the normal type tilt sensor, and further, a precise leveling is performed based on a detection result of the high accuracy tilt sensor.
For this reason, two types of tilt sensors with different accuracy are required, many components have been required, the structure becomes more complicated, and as a result, the manufacturing cost is increased.